scholarly journals Characterization of Vibrio cholerae O1 El TorgalU and galE Mutants: Influence on Lipopolysaccharide Structure, Colonization, and Biofilm Formation

2001 ◽  
Vol 69 (1) ◽  
pp. 435-445 ◽  
Author(s):  
Jutta Nesper ◽  
Crystal M. Lauriano ◽  
Karl E. Klose ◽  
Dagmar Kapfhammer ◽  
Anita Kraiß ◽  
...  
Keyword(s):  
Organic Acids ◽  
Vibrio Cholerae ◽  
Bile Salts ◽  
Short Chain ◽  
Core Oligosaccharide ◽  
O Antigen ◽  
Mouse Small Intestine ◽  
Vibrio Cholerae O1 ◽  
El Tor

ABSTRACT Recently we described the isolation of spontaneous bacteriophage K139-resistant Vibrio cholerae O1 El Tor mutants. In this study, we identified phage-resistant isolates with intact O antigen but altered core oligosaccharide which were also affected in galactose catabolism; this strains have mutations in the galU gene. We inactivated another gal gene, galE, and the mutant was also found to be defective in the catabolism of exogenous galactose but synthesized an apparently normal lipopolysaccharide (LPS). Both gal mutants as well as a rough LPS (R-LPS) mutant were investigated for the ability to colonize the mouse small intestine. The galU and R-LPS mutants, but not thegalE mutant, were defective in colonization, a phenotype also associated with O-antigen-negative mutants. By investigating several parameters in vitro, we could show that galU and R-LPS mutants were more sensitive to short-chain organic acids, cationic antimicrobial peptides, the complement system, and bile salts as well as other hydrophobic agents, indicating that their outer membrane no longer provides an effective barrier function. O-antigen-negative strains were found to be sensitive to complement and cationic peptides, but they displayed significant resistance to bile salts and short-chain organic acids. Furthermore, we found thatgalU and galE are essential for the formation of a biofilm in a spontaneous phage-resistant rugose variant, suggesting that the synthesis of UDP-galactose via UDP-glucose is necessary for biosynthesis of the exopolysaccharide. In addition, we provide evidence that the production of exopolysaccharide limits the access of phage K139 to its receptor, the O antigen. In conclusion, our results indicate involvement of galU in V. cholerae virulence, correlated with the observed change in LPS structure, and a role for galU and galE in environmental survival of V. cholerae.

scholarly journals Characterization of Vibrio cholerae O1 Antigen as the Bacteriophage K139 Receptor and Identification of IS1004Insertions Aborting O1 Antigen Biosynthesis

2000 ◽  
Vol 182 (18) ◽  
pp. 5097-5104 ◽  
Author(s):  
Jutta Nesper ◽  
Dagmar Kapfhammer ◽  
Karl E. Klose ◽  
Hilde Merkert ◽  
Joachim Reidl
Keyword(s):  
Vibrio Cholerae ◽  
Binding Studies ◽  
Core Oligosaccharide ◽  
O Antigen ◽  
Mouse Small Intestine ◽  
Normal Human ◽  
Vibrio Cholerae O1 ◽  
Phage Receptor ◽  
El Tor

ABSTRACT Bacteriophage K139 was recently characterized as a temperate phage of O1 Vibrio cholerae. In this study we have determined the phage adsorption site on the bacterial cell surface. Phage-binding studies with purified lipopolysaccharide (LPS) of different O1 serotypes and biotypes revealed that the O1 antigen serves as the phage receptor. In addition, phage-resistant O1 El Tor strains were screened by using a virulent isolate of phage K139. Analysis of the LPS of such spontaneous phage-resistant mutants revealed that most of them synthesize incomplete LPS molecules, composed of either defective O1 antigen or core oligosaccharide. By applying phage-binding studies, it was possible to distinguish between receptor mutants and mutations which probably caused abortion of later steps of phage infection. Furthermore, we investigated the genetic nature of O1-negative strains by Southern hybridization with probes specific for the O antigen biosynthesis cluster (rfb region). Two of the investigated O1 antigen-negative mutants revealed insertions of element IS1004 into the rfb gene cluster. Treating onewbeW::IS1004 serum-sensitive mutant with normal human serum, we found that several survivors showed precise excision of IS1004, restoring O antigen biosynthesis and serum resistance. Investigation of clinical isolates by screening for phage resistance and performing LPS analysis of nonlysogenic strains led to the identification of a strain with decreased O1 antigen presentation. This strain had a significant reduction in its ability to colonize the mouse small intestine.

scholarly journals Second-Generation Recombination-Based In Vivo Expression Technology for Large-Scale Screening for Vibrio cholerae Genes Induced during Infection of the Mouse Small Intestine

2005 ◽  
Vol 73 (2) ◽  
pp. 972-980 ◽  
Author(s):  
C. G. Osorio ◽  
J. A. Crawford ◽  
J. Michalski ◽  
H. Martinez-Wilson ◽  
J. B. Kaper ◽  
...  
Keyword(s):  
Vibrio Cholerae ◽  
Large Scale ◽  
Screening Method ◽  
Mouse Small Intestine ◽  
In Vivo Expression ◽  
Induced Genes ◽  
El Tor ◽  
Selection Of

ABSTRACT We have constructed an improved recombination-based in vivo expression technology (RIVET) and used it as a screening method to identify Vibrio cholerae genes that are transcriptionally induced during infection of infant mice. The improvements include the introduction of modified substrate cassettes for resolvase that can be positively and negatively selected for, allowing selection of resolved strains from intestinal homogenates, and three different tnpR alleles that cover a range of translation initiation efficiencies, allowing identification of infection-induced genes that have low-to-moderate basal levels of transcription during growth in vitro. A transcriptional fusion library of 8,734 isolates of a V. cholerae El Tor strain that remain unresolved when the vibrios are grown in vitro was passed through infant mice, and 40 infection-induced genes were identified. Nine of these genes were inactivated by in-frame deletions, and their roles in growth in vitro and fitness during infection were measured by competition assays. Four mutant strains were attenuated >10-fold in vivo compared with the parental strain, demonstrating that infection-induced genes are enriched in genes essential for virulence.

scholarly journals New Biotype of Vibrio cholerae O1 from Clinical Isolates in Surabaya

2010 ◽  
Vol 1 (1) ◽  
pp. 48
Author(s):  
Garry Cores De Vries ◽  
Emy Koestanti Sabdoningrum ◽  
Dadik Rahardjo
Keyword(s):  
Vibrio Cholerae ◽  
Clinical Isolates ◽  
Epidemic Strain ◽  
Surveillance Strategy ◽  
Pathogenic Variants ◽  
In Vitro Technique ◽  
Vibrio Cholerae O1 ◽  
Arbitrarily Primed Pcr ◽  
El Tor

A surveillance of new pathogenic variants of Vibrio cholerae O1 strains was initiated to identify the emerge and spread throughout Surabaya. Findings from seven years (1994–2000) and from years 2008 until now by using a two-fold surveillance strategy was pursued involving 1) hospital-based case recognition, and 2) environment samples. Rectal swabs and environment samples were transported to ITD-UNAIR, Surabaya for culture and isolates were characterized by serotypic identification and arbitrarily primed PCR fingerprints revealed a group of strains with similar fingerprint patterns that are distinct from those of the current El Tor epidemic strain. These strains have been analyzed by in vitro technique and the group has been denominated the Surabaya-Indonesian variant of V. cholerae O1.

Genomic Variability of Pathogenicity Islands in Nontoxigenic Strains of Vibrio cholerae O1 Biotype El Tor

2020 ◽  
Vol 56 (9) ◽  
pp. 1055-1069
Author(s):  
N. I. Smirnova ◽  
A. A. Kritsky ◽  
J. V. Alkhova ◽  
E. Yu. Agafonova ◽  
E. Yu. Shchelkanova ◽  
...  
Keyword(s):  
Vibrio Cholerae ◽  
Pathogenicity Islands ◽  
Genomic Variability ◽  
Vibrio Cholerae O1 ◽  
El Tor

Vibrio cholerae O1 El Tor variant and emergence of Haitian ctxB variant in the strains isolated from South India

2015 ◽  
Vol 205 (2) ◽  
pp. 195-200 ◽  
Author(s):  
Debdutta Bhattacharya ◽  
Shuchismita Dey ◽  
Gururaja Perumal Pazhani ◽  
Thandavarayan Ramamurthy ◽  
Mahantesh V. Parande ◽  
...  
Keyword(s):  
Vibrio Cholerae ◽  
South India ◽  
Vibrio Cholerae O1 ◽  
El Tor

scholarly journals Isolation of Vibrio cholerae O1 strains similar to pre-seventh pandemic El Tor strains during an outbreak of gastrointestinal disease in an island resort in Fiji

2006 ◽  
Vol 55 (11) ◽  
pp. 1559-1562 ◽  
Author(s):  
G. Balakrish Nair ◽  
Ashrafus Safa ◽  
N. A. Bhuiyan ◽  
Suraia Nusrin ◽  
Denise Murphy ◽  
...  
Keyword(s):  
Vibrio Cholerae ◽  
Gastrointestinal Disease ◽  
Vibrio Cholerae O1 ◽  
El Tor

scholarly journals Vibrio cholerae O1 em amostras de ambientes aquáticos e de alimentos analisados no Estado de Pernambuco, Brasil

1998 ◽  
Vol 14 (3) ◽  
pp. 465-471 ◽  
Author(s):  
Waldêny Colaço ◽  
Sandoval Vieira da Silva Filho ◽  
Dália dos Prazeres Rodrigues ◽  
Ernesto Hofer
Keyword(s):  
Vibrio Cholerae ◽  
Vibrio Cholerae O1 ◽  
El Tor

No período de 1992 a 1994, foram analisadas 2.585 amostras de águas de diferentes ecossistemas, acrescidas de 91 espécimens de alimentos visando ao monitoramento de Vibrio cholerae O1 no Estado de Pernambuco. Nas 2.676 amostras foram detectadas 193 cepas de Vibrio cholerae O1 (7,21%) com predominância do sorovar Inaba (183-94,8%) sobre Ogawa (10-5,1%), todas classificadas no biotipo El Tor e sensíveis à tetraciclina. Numa parcela de setenta amostras selecionadas ao acaso, mas incluindo todas do sorovar Ogawa, foi evidenciada a produção de toxina colérica. A maior incidência do vibrião colérico em águas de rios, canais e de esgoto, representando 86% dos isolados, indicou a contaminação fecal por excretores como a causa preponderante na disseminação da bactéria nos sistemas aquáticos. Assinala-se a discreta ocorrrência de V. cholerae O1 nos alimentos processados (2,1%).

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